package com.sky.aspect;

import com.sky.annotation.AutoFill;
import com.sky.constant.AutoFillConstant;
import com.sky.context.BaseContext;
import com.sky.enumeration.OperationType;
import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.Signature;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.stereotype.Component;

import java.lang.reflect.Method;
import java.time.LocalDateTime;

/**
 * 自定义注解实现公告字段自动填充处理逻辑
 */
@Aspect
@Component
@Slf4j
public class AutoFillAspect {
    /**
     * 切入点
     */
    @Pointcut("execution(* com.sky.mapper.*.*(..)) && @annotation(com.sky.annotation.AutoFill)")
    public void autoFillPointCut(){}

    /**
     * 前置通知，在通知中进行公共字段赋值
     */
    @Before("autoFillPointCut()")
    public void autoFill(JoinPoint joinPoint){

        //获取到当前被拦截到的数据库操作类型
        MethodSignature signature =(MethodSignature) joinPoint.getSignature();
        AutoFill autoFill = signature.getMethod().getAnnotation(AutoFill.class);
        OperationType operationType = autoFill.value();//获取操作类型
        //获取到当前被拦截到的方法的参数-实体对象
        Object[] args = joinPoint.getArgs();
        if(args == null || args.length == 0){
            return;
        }
        Object entity = args[0];


        //准备赋值的数据
        LocalDateTime now = LocalDateTime.now();
        Long currentId = BaseContext.getCurrentId();
        
        //根据当前不同的操作类型，为对应的属性通过反射机制来赋值

        if(operationType == OperationType.INSERT){
            //为四个公共赋值
            try {
                Method setCreteTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_TIME, LocalDateTime.class);
                Method setCreteUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_USER, Long.class);
                Method setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
                Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, Long.class);

                //通过反射为对象属性赋值
                setCreteTime.invoke(entity,now);
                setCreteUser.invoke(entity,currentId);
                setUpdateTime.invoke(entity,now);
                setUpdateUser.invoke(entity,currentId);
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        }else if(operationType == OperationType.UPDATE){
            try{
                Method setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
                Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, Long.class);

            } catch (NoSuchMethodException e) {
                throw new RuntimeException(e);
            }
        }
    }
}
